Multifunctional nanomaterials for smart wearable diabetic healthcare devices.

Wearable diabetic healthcare devices have attracted great attention for real-time continuous glucose monitoring (CGM) using biofluids such as tears, sweat, saliva, and interstitial fluid via noninvasive ways. In response to the escalating global demand for CGM, these devices enable proactive management and intervention of diabetic patients with incorporated drug delivery systems (DDSs). In this context, multifunctional nanomaterials can trigger the development of innovative sensing and management platforms to facilitate real-time selective glucose monitoring with remarkable sensitivity, on-demand drug delivery, and wireless power and data transmission.

Emerging strategies to fabricate polymeric nanocarriers for enhanced drug delivery across blood-brain barrier: An overview.

Blood-brain barrier (BBB) serves as an essential interface between central nervous system (CNS) and its periphery, allowing selective permeation of ions, gaseous molecules, and other nutrients to maintain metabolic functions of brain. Concurrently, it restricts passage of unsolicited materials from bloodstream to CNS which could otherwise lead to neurotoxicity. Nevertheless, in the treatment of neurodegenerative diseases such as Parkinson's, Alzheimer's, diffuse intrinsic pontine glioma, and other brain cancers, drugs must reach CNS.

Microwave-assisted rapid synthesis of nitrogen-enriched amphibious carbon quantum dots for sensitive detection of ROS and multiple other applications.

Carbon quantum dots (CQDs) have gained tremendous attention due to their pertinence in diverse application fields. Herein, we report the application of nitrogen-doped CQDs (N-CQDs) for the sensitive detection of reactive oxygen species (ROS) . The N-CQDs were synthesized a rapid, one-pot, cost-effective and environmentally friendly approach, and exhibited amphibious solubility in solvents with a wide range of relative polarities from 1 to 0.

pH-responsive polyelectrolyte complexation on upconversion nanoparticles: a multifunctional nanocarrier for protection, delivery, and 3D-imaging of therapeutic protein.

The delicate tertiary structure of proteins, their susceptibility to heat- and enzyme-induced irreversible denaturation, and their tendency to get accumulated at the cell membrane during uptake are daunting challenges in proteinaceous therapeutic delivery. Herein, a polyelectrolyte complex having encapsulated therapeutic protein has been designed on the surface of upconverting luminescent nanoparticles (NaYF:20%Yb,2%Er). This nanosized complex system has been found to overcome the challenges of protein aggregation at the cell membrane.

Polyelectrolyte-Dye Interactions: An Overview.

Polyelectrolytes are polymers with repeating units of ionizable groups coupled with counterions. Recently, polyelectrolytes have drawn significant attention as highly promising macromolecular materials with potential for applications in almost every sector of our daily lives. Dyes are another class of chemical compounds that can interact with substrates and subsequently impart color through the selective absorption of electromagnetic radiation in the visible range.

Structure-Based Varieties of Polymeric Nanocarriers and Influences of Their Physicochemical Properties on Drug Delivery Profiles.

Carriers are equally important as drugs. They can substantially improve bioavailability of cargos and safeguard healthy cells from toxic effects of certain therapeutics. Recently, polymeric nanocarriers (PNCs) have achieved significant success in delivering drugs not only to cells but also to subcellular organelles.

Hydrodynamic and conformational characterization of aqueous sodium alginate solutions with varying salinity.

Insight into the role of electrostatic interactions on the hydrodynamics and conformation of aqueous sodium alginate was gained through viscometry. Alginate chains are found to shrink in salt-free solutions more rapidly with increasing polymer concentration compared to salt-solutions. For salt-free solutions, a reduced polymer concentration of less than 1 suffices to make the alginate coil volume half of that at infinite dilution which becomes invariant when the reduced concentration exceeds 8.

Isoprocurcumenol Supports Keratinocyte Growth and Survival through Epidermal Growth Factor Receptor Activation.

Although proliferation of keratinocytes, a major type of skin cells, is a key factor in maintaining the function of skin, their ability to proliferate tends to diminish with age. To solve such a problem, researchers in medical and skin cosmetic fields have tried to utilize epidermal growth factor (EGF), but achieved limited success. Therefore, a small natural compound that can mimic the activity of EGF is highly desired in both medical and cosmetic fields.

Near-Infrared-Triggered Upconverting Nanoparticles for Biomedicine Applications.

Due to the unique properties of lanthanide-doped upconverting nanoparticles (UCNP) under near-infrared (NIR) light, the last decade has shown a sharp progress in their biomedicine applications. Advances in the techniques for polymer, dye, and bio-molecule conjugation on the surface of the nanoparticles has further expanded their dynamic opportunities for optogenetics, oncotherapy and bioimaging. In this account, considering the primary benefits such as the absence of photobleaching, photoblinking, and autofluorescence of UCNPs not only facilitate the construction of accurate, sensitive and multifunctional nanoprobes, but also improve therapeutic and diagnostic results.

Uptake of Polyelectrolyte Functionalized Upconversion Nanoparticles by Tau-Aggregated Neuron Cells.

Tauopathy is the aggregation phenomenon of tau proteins and associated with neurodegenerative diseases. It metastasizes via the transfer of tau aggregates to adjacent neuron cells; however, the mechanism has not yet been fully understood. Moreover, if the materials used for designing drug delivery system to treat such neurodegenerative diseases do not undergo biodegradation or exocytosis but remains in cells or tissues, they raise concerns about their possible negative impacts.

Designing Microparticle-Impregnated Polyelectrolyte Composite: The Combination of ATRP, Fast Azidation, and Click Reaction Using a Single-Catalyst, Single-Pot Strategy.

Polystyrene microparticles were covalently impregnated into the networks of functional polyelectrolyte chains designed via a tandem run of three reactions: (i) synthesis of water-soluble polyelectrolyte, (ii) fast azidation and (iii) a 'click' reaction, using the single-catalyst, single-pot strategy at room temperature in mild aqueous media. The model polyelectrolyte sodium polystyrenesulfonate (NaPSS) was synthesized via the well-controlled atom transfer radical polymerization (ATRP) whose halogen living-end was transformed to azide and subsequently coupled with an alkyne carboxylic acid through a 'click' reaction using the same ATRP catalyst, throughout. Halogen to azide transformation was fast and followed the radical pathway, which was explained through a plausible mechanism.

Cancer therapeutics with epigallocatechin-3-gallate encapsulated in biopolymeric nanoparticles.

With the recent quantum leap in chemoprevention by dietary products, their use as cancer therapeutics is garnering worldwide attention. The concept of effortlessly fighting this deadly disease by gulping cups of green tea or swallowing green tea extract capsules is appreciated universally. Epigallocatechin-3-gallate (EGCG), a major polyphenol in green tea, has generated significant interest in controlling carcinogenesis due to its growth-inhibitory efficacy against a variety of cancers by targeting multiple signaling pathways.

Long-Standing Stability of Silver Nanorod Array Substrates Functionalized Using a Series of Thiols for a SERS-Based Sensing Application.

Silver nanorod (AgNR) array substrates were fabricated using an oblique angle thermal evaporation technique; their long-term stability, surface uniformity and reproducibility, which are primary requirements for their widespread realistic application and commercialization, were assessed using surface-enhanced Raman scattering (SERS) spectroscopy. The nanorod surfaces were functionalized using a series of organic thiols, which range from hydrophilic to hydrophobic, to mimic various conditions that often arise during detection of hydrophilic/phobic analytes in a realistic application field. A group of these functionalized substrates was stored in ambient laboratory atmosphere; another in light minimized, moisture-free vacuum; while another was stowed carefully and neatly in water to mimic realistic conditions.

Morphological and SERS Properties of Silver Nanorod Array Films Fabricated by Oblique Thermal Evaporation at Various Substrate Temperatures.

Aligned silver nanorod (AgNR) array films were fabricated by oblique thermal evaporation. The substrate temperature during evaporation was varied from 10 to 100 °C using a home-built water cooling system. Deposition angle and substrate temperature were found to be the most important parameters for the morphology of fabricated films.

Apoptosis induced by para-phenylenediamine involves formation of ROS and activation of p38 and JNK in chang liver cells.

para-Phenylenediamine (p-PD) is a suspected carcinogen, but it has been widely used as a component in permanent hair dyes. In this study, the mechanism of p-PD-induced cell death in normal Chang liver cells was investigated. The results demonstrated that p-PD decreased cell viability in a dose-dependent manner.